Mitsubishi Colt Ralliart. Manual - part 528

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55A-20

Step 15. Check the blower switch continuity.
 Refer to 

P.55A-55

.

Q: Is the blower switch continuity in good condition?

YES : 

Go to Step 16.

NO : 

Replace the blower switch.

Step 16. Check the wiring harness between B-31 
blower switch connector terminal No.2 and B-116 
blower relay connector terminal No.4.

AC401055

Connector: B-31

AM

Harness side

B-31 (B)

AC313824

Connector: B-116

AD

Junction block side

Junction block (Front view)

NOTE: 

AC313826

Harness side

AE

Connector: B-130

Junction block (Rear view)

Prior to the wiring harness inspection, check junction 
block connectors B-130, and repair if necessary.

• Check the blower relay output line for open cir-

cuit.

Q: Is the check result normal?

YES : 

Go to Step 17.

NO : 

Repair the wiring harness.

Step 17. Check the wiring harness between B-10 
blower motor connector terminal No.1 and B-31 
blower switch connector terminal No.6.

AC401056

Connectors: B-10, B-31

AH

Harness side

B-10

B-31

B-10

Harness side

B-31

• Check the blower motor power supply line for 

open circuit.

Q: Is the check result normal?

YES : 

The trouble can be an intermittent 

malfunction (Refer to GROUP 00, How to 
Cope with Intermittent Malfunction 

P.00-13

).

NO : 

Repair the wiring harness.

Step 18. Check the blower fan and motor 
operation.
 Refer to 

P.55A-61

.

Q: Is the check result normal?

YES : 

The trouble can be an intermittent 

malfunction (Refer to GROUP 00, How to 
Cope with Intermittent Malfunction 

P.00-13

).

NO : 

Replace the blower motor.

Main

Index

Group

TOC

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55A-21

Inspection Procedure 5: The blower air volume cannot be changed

BLOWER
SWITCH

RESISTOR

BLOWER
MOTOR

Wire colour code
B : Black     LG : Light green     G : Green     L : Blue     W : White     Y : Yellow     SB : Sky blue
BR : Brown     O : Orange     GR : Gray     R : Red     P : Pink     V : Violet

BLOWER
RELAY

Blower Motor Circuit

COMMENTS ON TROUBLE SYMPTOM

If the blower air amount cannot be changed when the 
blower switch is operated, the blower switch may be 
defective.

TROUBLESHOOTING HINTS

• Malfunction of the resistor

• Damaged the wiring harness or connectors

• Malfunction of the blower switch

DIAGNOSIS PROCEDURE

Step 1. Check that the blower motor operates 
when the blower switch is moved to the "4 (HI)" 
position.
(1) Turn the ignition switch to the "ON" position.
(2) Turn the blower switch to the "4 (HI) " position.

Q: Does the blower motor operate when the blower 

switch is moved to the "4 (HI)" position?
YES : 

Go to Step 2.

NO : 

Refer to Inspection procedure 4 "The blower 
does not work 

P.55A-15

."

Main

Index

Group

TOC

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55A-22

Step 2. Connector check: B-31 blower switch 
connector

AC401055

Connector: B-31

AM

Harness side

B-31 (B)

Q: Is the check result normal?

YES : 

Go to Step 3.

NO : 

Repair the connector.

Step 3. Check the blower switch continuity.
 Refer to 

P.55A-55

.

Q: Is the blower switch continuity in good condition?

YES : 

Go to Step 4.

NO : 

Replace the blower switch.

Step 4. Connector check: B-04 resistor connector

AC401053

Connector: B-04

AF

Harness side

Q: Is the check result normal?

YES : 

Go to Step 5.

NO : 

Repair the connector.

Step 5. Check the resistor resistance value.
 Refer to 

P.55A-61

.

Q: Is the measured value at the standard value?

YES : 

Go to Step 6.

NO : 

Replace the blower resistor.

Step 6. Check the wiring harness between B-31 
blower switch connector (terminals 1, 4 and 5) 
and B-04 resistor connector (terminals 3, 1 and 
4).

AC401053

Connector: B-04

AF

Harness side

AC401055

Connector: B-31

AM

Harness side

B-31 (B)

• Check the blower switch output line for open cir-

cuit.

Q: Is the check result normal?

YES : 

Go to Step 7.

NO : 

Repair the wiring harness.

Step 7. Connector check: B-10 blower motor 
connector

AC401055

Connector: B-10

AL

Harness side

Q: Is the check result normal?

YES : 

Go to Step 8.

NO : 

Repair the connector.

Main

Index

Group

TOC

TROUBLESHOOTING

HEATER, AIR CONDITIONER AND VENTILATION

55A-23

Step 8. Check the wiring harness between B-10 
blower motor connector terminal No.1 and B-04 
resistor connector terminal No.2.

AC401053

Connector: B-04

AF

Harness side

AC401055

Connector: B-10

AL

Harness side

• Check the blower motor power supply line for 

open circuit.

Q: Is the check result normal?

YES : 

The trouble can be an intermittent 

malfunction (Refer to GROUP 00, How to 
Cope with Intermittent Malfunction 

P.00-13

).

NO : 

Repair the wiring harness.

Main

Index

Group

TOC